1. Field of the Invention
This invention relates generally to vending machines having helical dispensing coils, and more particularly to an improved shelf configuration for the forward end of a product shelf in such a machine comprising an improved support member for rotatably supporting the front end of an elongated helical coil above the surface of the shelf and the forwardmost convolution of the coil is not supported by the support member.
2. Description of the Prior Art
The use of helical coils in vending machines as a means for transporting articles to be vended from a location in the interior of the machine to a discharge point is well known. Typically, the vending coil is used in conjunction with a horizontal support tray or shelf. The articles to be vended are placed within the convolutions of the vending coil and are supported by the tray or shelf. Upon rotation of the vending coil, the articles to be dispensed is longitudinally advanced along the shelf until it reaches the front end of the shelf. Upon further rotation of the vending coil, the article to be dispensed is forced over the front edge of the shelf and falls into a discharge bin where it may be manually removed by the person operating the vending machine.
U.S. Pat. No. 3,993,215 to Cox et al illustrates a vending coil support structure typically used in the prior art. In the Cox structure, the dispensing coil rides within a trough formed within a shelf. The forward end of the shelf is configured to form a notch, when viewed above, with a forwardly projecting ledge at one side of the notch. The dispensing coil is disposed with its forward end extending over the notch and the lower end of its forwardmost convolution extending over the notch to support the next item to be dispensed at one side thereof above the notch, with the other side of the item being supported on the projecting ledge. During a dispensing cycle, as the coil rotates, the lower convolution portion which supports the item to be dispensed is withdrawn from beneath the item, allowing the item to tip sideways and to fall under the force of gravity through the notch and into an underlying collection bin.
The Cox apparatus was specifically designed for vending machines having relatively closer tolerances between the front of the helix and the front door of the cabinet, where it is desirable to cause the item being dispensed to tip to the "side" rather than "forward" during the dispensing cycle. This apparatus was particularly designed for dispensing relatively light-weight bag packaged articles such as potato chips, pretzels and the like whch would have a tendency to hang-up or become bridged between the shelf and the front door of the machine, if such articles would be dispensed so as to tip-over the forward longitudinal direction of the coil. While the side-tipping dispensing apparatus of Cox addressed the bridging problem associated with dispensing bag-type articles, the structure was susceptible to jamming or catching of the bag-type package being dispensed between the lower surface of the dispensing coil and the upper surface of the trough.
The inventor's prior U.S. patent application Ser. No. 669,348 filed Mar. 22, 1976, now issued as U.S. Pat. No. 4,061,245, described an improved helical-coil dispensing apparatus, generally operable in a side-tipping manner, which overcomes the jamming or catching deficiencies of the Cox-type apparatus. This apparatus does not require a coil-guide trough along the entire length of the dispensing coil, but has means for supporting the opposite ends of the dispensing coil such that the lowermost portions of the opposite ends are exposed above and spaced from the horizontal shelf surface on which the items to be dispensed are being supported. A coil support member mounted at the forward end of the shelf is configured to rotatably support the forward end of the coil such that the lower extremity of the coil does not engage the shelf surface, and thus cannot catch the package of the article being dispensed therebetween.
One type of such support member of the forward end of the dispensing shelf is disclosed in FIGS. 4-6 of the inventor's above-referenced prior patent. Such a support member includes two parallel, transversely spaced coil support members having upper planar surfaces disposed above the level of the shelf surface, for supporting the dispensing coil thereon. A first end of each of the coil support members is provided with an upwardly extending ramp which guides articles to be dispensed and moved by the coil from the primary shelf surface to the upper planar surfaces of the coil support members. A second end of one of the support members projects outwardly beyond the front end of the shelf, and the second end of the other coil support member terminates at a position approximately coincident with the front edge of the shelf. This forms, in effect, a laterally offset notch as viewed from above, at the forward end of the shelf. The article to be next dispened is supported and dispensed in a manner similar to that above-described with respect to the Cox apparatus.
The inventor's prior U.S. patent application Ser. No. 389,817 filed Oct. 6, 1977, now issued as U.S. Pat. No. 4,148,412, described a support apparatus comprising a first elongated coil support member transversely spaced from and parallel to a second elongated coil support member. The coil support members each terminated at coplanar ends which are connected together by means of a downwardly inclined ramp. One of the coil support members adjacent the downwardly inclined ramp has a beveled inner edge portion to allow at least some products moved by the coil to be oriented in a transversely tilted position immediately before dispensing. The coil support members were transversely spaced apart at a sufficient distance so as to cause the front portion of the dispensing coil to be supported by the upper planar surfaces of the coil support members, at a position spaced above the shelf space. However, the coil was still carried along its entire length by at least one of the coil support members. While this invention overcame the deficiencies of the prior art helical coil dispensing structures for dispensing heavy or boxed items, the support of the coil along its entire length provided for an opportunity for relatively light-weight bag packaged type items such as potato chips and pretzels to become caught at the dispensing end between the coil and the support member.
The present invention overcomes the deficiencies of the prior helical coil dispensing structures.